DE 198 46 450 A1 describes a switch module system having two switch modules. The first switch module is an electromechanical switch module having a switch. The second switch module is a mechanical switch module having at least one switch actuator. The switch and the at least one switch actuator can be connected to one another. The electromechanical switch module includes a flexible printed circuit board and can have an elastomeric mat. One or more keys belong to the mechanical switch module. This switch module system enables different electromechanical and mechanical switch modules to be combined with one another. Each respective combination has an external housing that can contain one or more switches.